1. Field of the Invention
The present invention relates to a half fit preventive connector which separates them from each other to thereby recognize that they are fitted with each other imperfectly in case where the two connectors are imperfectly engaged, and secures them to each other unremovably in case where the two connectors are engaged perfectly, when a set of male and female connectors are fitted with each other.
The present application is based on the Japanese Patent Application No. 2000-167539 which is incorporated herein by reference.
2. Description of the Related Art
Conventionally, in a vehicle such as a car, when connecting wires together or connecting together various pieces of electronic equipment, there is often used a connecting method in which they are connected together by fitting a set of male and female connectors with each other. When a set of male and female connectors are fitted with each other, in case where they are half fitted (imperfectly fitted), connecting terminals respectively stored within the two connectors are imperfectly connected with each other, which causes poor contact between them or, what is worse, causes the two connectors to be separated from each other; and, as a result of this, there is a fear that the vehicle fails to run.
To solve the above problems, conventionally, there has been proposed a connector lock mechanism for preventing the connector imperfect fit. Description will be given below of an example of the conventional connector lock mechanism with reference to FIGS. 8 and 9.
In a connector lock mechanism 41 shown in FIG. 8, of a set of male and female connectors 42 and 43, one male connector 42 is extended along the fitting direction (in FIG. 8, the direction of an arrow mark B) where it is fitted with the other female connector 43, and includes a pair of flexible arms 45 and 46 each with an engaging portion 48 formed in the leading end portion thereof. Also, the male connector 42 further includes a terminal storage chamber 42a; and, in the terminal storage chamber 42a, there are stored two female-type terminals.
The two flexible arms 45 and 46 respectively rise from the rear end side of the upper wall of the housing of the male connector 42 and are extended toward the front end side of the housing upper wall, while the rising base portions of the two flexible arms 45 and 46 join each other to provide a united body. Also, the two flexible arms 45 and 46 are spaced apart from each other in the lateral direction of the connector 42 and are arranged in parallel to each other. The two engaging portions 48 are respectively projections which project outwardly in the lateral direction of the connector 42 from the leading end portions of their associated flexible arms 45 and 46; and, each projection 48 includes a tapered surface which is gradually inclined outwardly from the front end side of the connector housing toward the rear end side thereof.
The female connector 43 comprises a pair of arm guide surfaces 50 and 51 respectively including securing means which not only allow the flexible arms 45 and 46 to flex until the connector mutual fit length reaches a specified length, in other words, until the two connectors are fitted with each other perfectly but also, when the male connector 42 is inserted up to the perfect fit position of the female connector 43, lock the connector fitted state. The female connector 43 stores therein two male-type terminals corresponding to the two female-type terminals of the male connector 42 with which the female connector 43 is to be fitted.
Next, description will be given below of the fitting operation of the male and female connectors 42 and 43.
In the fitting operation starting stage of the male and female connectors 42 and 43, the male connector 42 is fitted into the female connector 43 in such a manner as shown by an arrow mark B. In this case, the two engaging portions 48 formed in the leading end portions of the pair of flexible arms 45 and 46 are respectively inserted into their associated arm guide surfaces 50 and 51 but, in this stage, they are not yet flexed or deformed.
And, in case where the insertion of the male connector 42 is kept on, as shown in FIG. 9, the pair of flexible arms 45 and 46 are flexed and deformed inwardly according to the inclination of the arm guide surfaces 50 and 51. Since the pair of flexible arms 45 and 46 are respectively formed elastic, in these arms 45 and 46, there is generated repulsive force which allows them to return back to their original shapes and thus, due to this repulsive force, the male connector 42 is pushed back in the direction of an arrow mark F shown in FIG. 9.
Therefore, in case where the insertion of the connector 42 is stopped while the two engaging portions 48 formed in the pair of flexible arms 45 and 46 are respectively in contact with the arm guide surfaces 50 and 51, the male connector 42 is removed from the female connector 43, thereby being able to prevent the imperfect fit between the male and female connectors 42 and 43.
And, in case where the male connector 42 is fitted into the female connector 43 perfectly, the two engaging portions 48 respectively get over their associated arm guide surfaces 50, 51 and are then secured to securing means 53, thereby holding the male and female connectors 42 and 43 in a perfectly fitted state where disengagement between the two connectors is impossible. In this state, a connecting terminal embedded in the male connector 42 is contacted with a male-type terminal 55 embedded in the female connector 43, so that the two connectors 42 and 43 are electrically connected with each other.
In the above-mentioned connector lock mechanism, since the repulsive force, that is, the force to separate the male and female connectors 42 and 43 from each other is simply generated by the mutual contact between the pair of flexible arms 45, 46 and the pair of arm guide surfaces 50, 51, the repulsive force is weak.
Therefore, in case where the insertion of the male connector 42 is stopped in a state that the male connector 42 is inserted into the female connector 43 to a certain degree, there is a possibility that the male connector 42 cannot be pushed back and thus an operator can mistake such imperfect fit for perfect fit.
In case where the above-mentioned imperfect fit is left as it is, not only poor electric contact can occur between the two connectors but also the mutual fit between them can be removed during use, thereby raising a fear that the vehicle can fail to run.
Also, in the fitting operation starting stage of the male and female connectors 42 and 43, since the projecting length of the male connector 42 from the female connector 43 can be clearly confirmed through visual observation, there is no possibility that the operator can mistake the imperfect fit for the perfect fit.
On the other hand, in a stage where the fitting operation of the two connectors has advanced, it is difficult for the operator to judge through visual observation whether the connector fitted state is perfect or not. And, in the case of the imperfect fit, the male and female connectors must be positively separated from each other. However, in the above-mentioned conventional connector lock mechanism, actually, for the above-mentioned reason, the male and female connectors are easy to be fitted together imperfectly.
The present invention aims at eliminating the above drawbacks found in the conventional connector lock mechanism. Accordingly, it is an object of the invention to provide a half fit preventive connector which, when fitting male and female connectors with each other, is positively capable of preventing the male and female connectors from being fitted together imperfectly.
In attaining the above object, according to the invention, there is provided a half fit preventive connector structured such that in one of a set of male and female connectors, there is disposed a flexible arm including an engaging portion in the front end portion thereof and extending in the connector fitting direction and, in the other connector, there are formed an arm guide surface for allowing the flexible arm to flex and deform until the set of male and female connectors are perfectly fitted with each other to thereby urge one connector in the opposite direction to the fitting direction, and a securing step portion for securing the engaging portion when the male and female connectors are perfectly fitted with each other, wherein the other connector includes an inclined projection having a tapered surface for allowing the flexible arm to flex until the attainment of the perfect fit to thereby generate repulsive force for promoting the urge of one connector in the opposite direction to the fitting direction, the inclined projection, in the case of the above-mentioned perfect fit, being capable of removing the promotion of the repulsive force and securing the engaging portion to the securing step portion.
According to the above-structured half fit preventive connector, as the male and female connectors are fitted with each other, a pair of flexible arms are respectively contacted with their associated arm guide surfaces and are thus flexed and deformed inwardly to thereby generate repulsive force for returning the male and female connectors back to their original shapes, while this repulsive force acts on the male and female connectors to separate them from each other. And, in case where the flexible arms are flexed and deformed, the one-end portions of the engaging portions formed in the end portions of the pair of flexible arms, that is, the contact portions of the flexible arms are contacted with the tapered surface of the inclined projection, so that the flexible arms are flexed and deformed in a different direction from a direction where the flexible arms are flexed under the guidance of the arm guide surfaces.
Therefore, since the pair of flexible arms are flexed and deformed in the two different directions respectively due to the arm guide surfaces and the tapered surface of the inclined projection, the repulsive force generated in connection with the tapered surface is added to the repulsive force generated in connection with the arm guide surfaces, which can promote the repulsive force to separate the male and female connectors from each other. Thus, in case where the fitted state of the male and female connectors is imperfect, these two connectors can be positively separated from each other, thereby being positively able to prevent the two connectors from being fitted together imperfectly.
Also, according to another aspect of the invention, in the above-mentioned half fit preventive connector, preferably, each of the engaging portions formed in the end portions of the flexible arms may include a curved-surface-shaped contact portion which, when executing the fitting operation, allows the flexible arm to slide smoothly on the tapered surface.
According to the above-structured half fit preventive connector, since the sliding motion between the engaging portion and tapered surface is performed with a low fitting force, the efficiency of the connector fitting operation can be enhanced.